DESCRIPTION (adapted from the application) Anorexia Nervosa (AN) is a psychiatric illness that is characterized by extreme weight loss and severe body image distortions. The purpose of this Mentored Patient-Oriented Research Career Development Award (MPORCDA) is to develop and execute a program of research that will investigate the potential biological predispositions that contribute to the difficulty patients have in maintaining normal weight, with the long-term goal being to design treatment strategies to address the biological abnormalities. More specifically, it will test the hypotheses that 1) Weight-restored patients with anorexia nervosa have elevated resting energy expenditure (REE) compared to controls 2) Weight-restored patients with anorexia nervosa have a central distribution of body fat compared to controls 3) Weight-restored patients with anorexia nervosa who gain the most fat centrally will have the least improvement on psychological measures 4) Weight-restored patients with AN have leptin levels out of proportion to body fat mass. It will also investigate the relationship between REE and leptin with respect to return of menses. Under the strong mentorship of Dr. B. Timothy Walsh (for clinical research training and expertise in Anorexia Nervosa), Dr. Rudolph L. Leibel (for the metabolic aspects of body weight regulation and obesity), and Dr. Richard N. Pierson (for assessment and application body composition measurement), this MPORCDA will provide the principal investigator with the skills and further experience to integrate the advances of the fields of anorexia nervosa, obesity and weight regulation, and body composition. The long-term goal of this award is for the candidate to become an expert and independent researcher in the psychobiology of weight regulation and body composition assessment, with special application to anorexia nervosa.